When we think of what to do with blackberries, custards aren't typically what comes to mind. Jam? Sure. Cobbler? You bet. But a pudding or ice cream? Not so much.
It makes sense, in a way. Blackberries are juicy, explode-y things full of seeds that get in the way of the pale creamy swirls of custard. Blackberries are all summer mess. Custards, however humble, feel somehow refined.
The exception to this is a blackberry swirl, used in cream pies, cheesecakes, and—to great effect—ice cream. I want my explode-y, jammy mess of fruit right now, but it's also a bajillion degrees outside, and I want my ice cream too. So here's this recipe, which is at once a fresh breath of summer breeze and also a rich, frosty, custardy scoop.
The base is steeped with generous amounts of lemon peel and minced ginger, mild enough to keep the blackberry the star, but assertive enough to add some citrus brightness and a slight spicy bite. Don't bother zesting the lemons; just peel off the yellow skin with a vegetable peeler, making sure to leave the white pith behind. The larger chunks will be easier to strain out.
Turning 3 1/2 cups of blackberries into a dark, intense 1/2 cup of swirl isn't difficult at all, but requires some care. Purée your blackberries just enough to loosen the juice; it'll be easier to strain out the larger chunks of pulp and seeds. And save adding sugar to the syrup until the very end. With this much of a reduction, it's easy to burn all that sugar. Even careful heat management can introduce more caramelized, less fruity flavors than you'd like for this application.
Making the actual swirl is even easier. Just don't think swirl—think layers. Spoon your churned ice cream into a container in thirds, and add the syrup in equal amounts between the layers. The motion of your scoop will be enough to create that pretty swirl effect.
- 2 cups heavy cream
- 1 cup whole milk
- Peels of two large lemons, removed with a vegetable peeler
- 3 tablespoons minced ginger
- 3 1/2 cups blackberries (about 18 ounces)
- 1 1/4 cup sugar, divided
- 3/4 teaspoon kosher salt, divided
- 6 egg yolks
In a heavy saucepan, bring cream and milk to a simmer. Stir in lemon peels and ginger, cover, and remove from heat. Let steep for 1 hour.
Purée blackberries in a blender or food processor just until they break apart into a liquid and no large chunks remain (see note). Slowly pour purée through a strainer and gently stir with a fork or whisk. Measure out 1 1/2 cups strained juice and discard blackberry pulp.
In a heavy saucepan, bring strained blackberry juice to a simmer on medium heat and reduce to 1/2 cup, stirring frequently. Stir in 1/2 cup sugar and 1/4 teaspoon salt until dissolved. Transfer to a small container and chill in refrigerator.
In a clean, heavy saucepan, whisk together 3/4 cups sugar with egg yolks until pale in color and thickened. When dairy finishes steeping, pour through a strainer into pot and whisk to combine with yolk-sugar mixture. Put saucepan on medium heat and cook, stirring frequently, until a custard forms on the back of a spoon, but a finger swiped across the back leaves a clean line. Add 1/2 teaspoon salt. Pour through a stainer into an airtight container and refrigerate overnight.
The next day, churn in ice cream maker according to manufacturer's instructions. While ice cream is churning, remove blackberry syrup from freezer and stir to loosen. Transfer 1/3 of finished ice cream into an airtight container, then quickly spread on half of syrup. Repeat, and top off with last 1/3 of ice cream. Chill in freezer until firm, at least three hours, preferably longer.
It's best to leave your blackberry purée slightly chunky, as it will be easier to strain and yield a better swirl.